问题
选择题
_______, the disease will produce a kind of poison that will kill the patient.
A．If it untreated
B．If is untreated
C．If being untreated
D．If untreated
答案
答案：D
这题考查if条件句的省略式：当主从句的主语一致时，可以省略主语和be动词，If untreated="if" the disease is treated，句意是：如果这个病不治疗的话会产生一种毒药制人的命。选D